Locking device for lamp-sockets.



incassa.

GUSTAF I. SILBERT, OF CHICAGO, ILLINOIS.

LOCKING DEVICE FOR LAMP-SOCKETS.

To all 'whom it may concern.' i

Be it known that l, GUsTAF I. SILBERT, a citizen .of the United States,and a resident of Chicago, in the county of Cook and State of Illinois,have invented certain new and useful Improvements in Locking Devices forLamp-Sockets; and I do hereby declare that the following is a full,clear, and exact description thereof, reference being had to theaccompanying drawings, and tothe letters of reference marked thereon,which forma part of this specification.

This invention relates to improvements in locking devices for lampsockets and consists of the matt-ers hereinafter described and moreparticularly pointed out in the appended claims.

`The object of the invention is to provide means in a. lamp socketoperable by a key inserted into. the socket from the outside thereof forlocking a lamp in the socket so that it may not be removed except by theuse of a key. p

My invention belongs to that particular type. of lock socket in which aset-screw is made use of to lock a lamp bulb in the socket and theinvention lies in the provision of means which will prevent anypossibility of electrical connection between the key and one of the lampcontacts through the setscrew which comprises the locking device.

The advantages of my invention will appear as I proceed with myspecification.

In the drawings :Hlligure 1 is a view representing a sectional view ofa-lamp socket provided with my improved locking device7 Specification ofLetters Patent.

Application filed October 18, 1912.

the lamp socket'in this case being made ofl insulatin -material. Fifi'.2 is a view re re- -senting a section through llig. l., on the line 2-2thereof. Fig. 3 lis a view representing a section parallel to that shownin Fig. 2, in a plane indicated by the line 3-8 ot' Fig. 1. Fig. 4 is aview representing an outside elevation of that part of the socketcontaining the aperture through which the key is in tended to beinserted. Fig. is an elevation of the key. Fig. 6 is a view similar toFig. 1, showing the construction applied to a socket having a metalyshell.

Referring now to that embodiment of my invention illustrated in` thedrawings and particularly that shown in Figs. 1 to 5, in elusive, 10indi cates the ser ich in this case is made of' insulating ir l;threaded contact shell container in a recess 1n said socket in the usualmanner' 12 a 11, the

Patented July "l, 191e.

serial No. 726,448.

lamp bulb, and 13 the threaded shell contact of said lamp bulb 'adaptedfor engagement within the contact shell 11 of the socket.

14 indicates an internally threaded sleeve inserted through an aperturein the socket wall and llined therein in any convenient manner. Saidsleeve is made of metal and has threaded into it a plug l5. vSaid plug15 has a recess 16 in its end nearest the recess in the lamp socket andin said recess is mounted a pin 17 having au enlarged-head- 18 of lessdiameter than that of the recess in the plug, so that an annularinsulating air -space is left, as shown, between the periphery of saidhead and the inner surface of the plug 16. The projecting edges of thehead 18 are engaged between an insulating' disk 19 located in the bottomofthe recess 16v and an apertured disk'of insulating material 2O againstwhich the recessed end of the plug is upset to provide engaging parts21.

By means of this construction the pin is same time is insulated thererom. The head of the plug is provided with diametrically oppositeapertures 22 (see Fig. 4) which are adapted to be engaged by pins 23 onthe end of a key 24, so constructed that it maybe in serted through theouter-end of the sleeve 14. As shown, the sleeve 111 has a wall 14a atits outer end in which is cut an oblong key-hole 25 through which thekey may be inserted. The pin 17 being made rigid with the plug 16, asdescribed, it is apparent that by inserting the key with its pins 23engaged in the holes 22 of the plug, said plug 16 and pin 17 mayberotated together in the manner of a set-screw so as to move said pintoward or away from the contact shell of the lamp bulb. The socketcontact shell 11 is provided with an aperture 11a in line withv thepin-17 sothat said pin may be brought into direct engagement with thecontact shell of the lamp bulb. Although Lthe pin 17 comes intoengagement with the contact shell of the lamp bulb and therefore intocircuit with one of the lamp terminals, since said pin is entirelyinsulated from the plug and the-sleeve in which said plug is engaged, itis apparent that there is no danger of an electric circuit beingmaintained through the key to the hand of the one who operates it..

ln Fig. 6, my invention is illustrated in connection with. a lamp sockethaving a metallic shell.v The construction in this case rigidly clampedwithin the lug and at the '20 with an aperture,v

threaded shell contact adaptedto be screwed into the shell contact ofsaid socket,a set-- is the same asin that just described, the

parts being indicated as before. The lamp socket in this case has ametallic Shell 10a. '14? indicates. thesleeve which is provided .5 withan' annular flange 14V secured against the inner surface of the shell10n and pr.o-

construction and arrangement, it is to be understood that the inventionis not limited thereto except as hereinafter pointed out in l5 theappended claims.

l `claim as my inventionz l 1. A locking device for lamp bulbscomprising, in combination with a socket, a recessed shell contact fixedtherein provided a' lamp bulb having a screw having threaded engagementwithin said socket and projecting through the aper? ture in said socketcontact shell, said set screw being adapted for engagement with thejsaid threaded shell contact of thelamp, key 'adapted to be inserted inthe loutside socket shell with said f a's my invention of saidf'socketto rotate said set-screw, and

means providing msulation between said setescrew, socket and key.

2. A locking device for prising, in combination with a socket, arecessed shell contact fixed therein, provided with an aperture,threaded shell contact adapted to be screwed into the shell Contact ofsaid socket, an internally threaded sleeve fixed to saidv socketadjacent said recess, a recessed plug threaded intosaid sleeve, a pinfixed in said plug so as to move therewith, means insulating said pinfrom said plug, and a key adapted to be inserted through the outer endof said sleeve and to be engaged against the outerl end of said plug tobring said pin into en-` gagement through the aperture in Said contactshell of the lamp. l

. In testimony, that'I elaimthe .foregoing presence of two witnesses,October, A. D. 1912. y

GUSTAF I. SILBERT.

this 15th day of Witnesses GEORGE R. WILKINS, T. H. ALFREDS.

lamp bulbs coin-V a lamp bulb having a I aflix my signaturel inthe

